One of the greatest benefits of the worlds of cognitive science and teaching becoming more closely aligned, has been that a profession that relies so heavily on effective explanations has been given clear guidance on how to do it successfully.

Dual Coding Theory, as first described by Allan Paivio in 1971, is a key example of how classroom practitioners can exploit this cross-over to their advantage when attempting to explain.

Oliver Caviglioli gives an excellent summary of the theory in this short clip. He says: “Humans receive new information from the environment in either visual or verbal formats. There are others but these two are the most fundamental. Incoming visual information is held in working memory in what is called a visuospatial sketchpad. And incoming verbal information is held and processed in an auditory loop. Both are limited in storage capacity, and both are separate. These two channels are independent of each other but do form, at moments, links, or associations. When images are linked in this way to words, they enrich the encoding process — otherwise known as learning.”

To simplify this further, we are able to accept both visual and verbal inputs at the same, thereby increasing our learning bandwidth. Furthermore, we can accept a greater capacity of visual input at one time compared with verbal input.

This then is how Dual Coding connects to explanation. As teachers we are constantly attempting to explain ideas that are clear to us, to those that are unfamiliar with them. This is a difficult process and as a result our explanations do not always work. Improving explanation is multi-faceted, however, by combing visual and verbal input we can increase the chances of explanations hitting the mark.

To support this, here are five practical tips for how we might use Dual Coding to achieve more successful explanations:

1. Explain over images, but never text:

If you explain while either projecting text or expecting students to read, you will create cognitive overload and reduce the likelihood or your explanation being accurately remembered. However if you have an image that represents the concept, and your explanation accompanies this, you can exploit the Dual Coding effect. For example if you wanted to explain the context of Wilfred Owen’s war poetry you could do so while projecting an image of a gas attack on a First World War trench.

2. Plan it:

If you are coming up to teaching a concept that you know students struggle with, plan your explanation incorporating visual images that you intend to draw live while explaining. This planning could be done individually, or even better, with your department. This will ensure you avoid the risk of Dual Coding becoming a barrier rather than a help to your explanation, as you attempt to think of, effectively draw, and explain tricky concepts at the same time. By planning them and practising them you will only need to concentrate on the explanation itself.

3. Cut content:

When planning an upcoming lesson that uses a resource that you made or used previously (an information sheet or a PowerPoint slide for example) go through a process of cutting the content it contains. Focus on having a fewer long sentences and ensure key concepts are chunked under sub-headings. If the resource contains largely text, replace as much of this as you can with images.

4. Case Study Diagrams:

This is a strategy taken directly from Durrington’s geography department. When explaining a geography case study (although this could be used in any subject that uses case studies) the department co-create a diagram to represent the case study. The diagram includes both words and pictures. Furthermore, certain generic images are used to communicate common themes within the case studies, for example a gravestone for death toll. A labelled example is shown below:

These are then used both in lessons and also for homework and revision.

5. Allow students to use both words and images when making notes:

If you want students to re-format or revise information, set them a task that requires them to use both images and words. For example when asking students to produce a mind map you could ask them to make every one of the key heading an image, and then the key details from it the text. Alternatively you could scaffold this by doing the first step yourself. An example of this when teaching the causes of the boom in the US economy in the 1920s would look like this: